body {
  font-size: 14px;
  color: #666;
}
header {
  height: 40px;
  background-color: red;
  display: flex;
}
header .logo {
  width: 70px;
  display: flex;
  justify-content: center;
  align-items: center;
}
header .logo i {
  width: 57px;
  height: 21px;
  background-image: url("../images/jd-sprites.png");
  background-size: 200px 200px;
  background-position: 0 -110px;
}
header .login {
  width: 50px;
  font-size: 14px;
  color: #fff;
  display: flex;
  justify-content: center;
  align-items: center;
}
header .search {
  flex: 1;
  padding: 5px 0;
  position: relative;
}
header .search::before {
  content: "";
  position: absolute;
  top: 10px;
  left: 11px;
  width: 20px;
  height: 20px;
  background-image: url("../images/jd-sprites.png");
  background-size: 200px 200px;
  background-position: -60px -110px;
}
header .search input {
  width: 100%;
  height: 100%;
  border-radius: 15px;
  text-indent: 30px;
}
/* 导航 */
nav {
  display: flex;
  flex-wrap: wrap;
}
nav a {
  width: 25%;
  text-align: center;
  padding: 5px 0;
}
nav a img {
  width: 50%;
  display: inline-block;
}
